Tim Shorts asked about rations. Well, bacon. But he meant rations. Mmm . . . bacon.
"How often do you have a party keep track of food? Do you make them take supplies for a two week trek they are about to begin? Or is that something you just hand wave?"" - Tim "1 is the loneliest number" Shorts
Yes, we track it. I tend to abstract a lot, but I don't abstract consumables.
Yet at the same time, when we do our megadungeon delving, it's not like the number of rations is a limiting factor. But it could be. It might be important if PCs want to bribe denizens with food ("Hey, want some trail mix?"), get stuck ("So, the runes say this door will re-open automatically in three days"), or otherwise end up needing food.
Not only that, we've recently had a significant wilderness component to our adventures. In these recent sessions, food is critical. So much so our recent addition, Dave the Knight, had to be sponsored for food by an ally* in order to make to the dungeon and back.
Dealing with ration replacement is a pain, though.
So we abstracted it down a little.
We figure you eat your rations during your downtime, and replace them with new ones. Thus, the cost of replacing any "spare" rations (ones brought back to town) is zero. Pretty much, this means you don't have to pay for rations for day trips, they are rolled into your weekly upkeep (base $150).
If you eat special rations - Elven rations, Dwarven rations - you have to pay the extra cost as additional upkeep. Paying an extra $30 for your special rations? Pay an extra $30 for upkeep.
Dwarven rations come with a weekly cost, since eating them weekly gives a Resistance.
All of this works because GURPS Dungeon Fantasy assumes a basic $150/week for upkeep. Or, between delves, in our case, since "per week" didn't work well with our 1 real day = 1 game day tracking method.
You know what we don't track? Water. Generally, it's been available. That will change in a desert, of course. We track what matters, when it matters.
How has this worked in actual play?
Quite well. We've adjusted a couple of PC's weekly upkeep costs. We had a few teething issues with an actual need to stock up on rations (in the Cold Fens, largely), and one or two with confusion over the pricing of special rations. But it hasn't been a real issue. It worked out quickly.
Overall this allows food to be a valued commodity and a potentially useful tradeoff of cost and weight vs. lower encumbrance, but not something we need to tick off ration by ration.
* Paid for by his dad's PC. Like Chris Rock says, "You're supposed to care for your kids." We'll still give Gerry the cookie.